Why is "peer review" a basis for scientific truth?

I often see evolutionists discounting creationists based on their statement that "creation scientists don't meet the peer review smell test." so is this a valid argument? Here is a list of Darwin's peers who gave him a poor review: Sir John Hershel, math; James Clerk Maxwell, physics; William Whewell, philosophy; Adam Sedgwick, geology; Andrew Murray, entomology; Richard Owen, coined 'dinosaur"; Louis Pasteur, immunization and Law of Biogenesis; and these are just a few. Want to know who was on Darwin's side of the argument, pastors of the Christian church. Frederick Farar, James Orr, Henry Drummond, A.H. Strong, and Henry Ward Beecher, all famous pastors of the day. Now I don't know what this means about evolution, but it does mean that "peer review" should not be the test for validity.